The development of environmentally friendly personal care products is very important in today's society. Environmentally friendly personal care products are not only desired to meet the needs of environmentally conscious consumers, they will likely be required by law in the future. Current personal care products are made from a combination of pulp, super-absorbents, elastomers, film, adhesives, and nonwoven components. The films and nonwovens are comprised mainly of polyolefins including polypropylene and polyethylene. After use, products are placed in landfills where they do not appreciably degrade over time. Though this type of landfill disposable is acceptable now, it is likely that landfill space will become scarce in the future and regulations will be created to limit the amount of products to be disposed of in this way. In Europe and Asia, where space is significantly limited compared to the U.S., regulations are already in development. In view of this, it is important to develop personal care products that degrade after use.
Disposable absorbent products currently find widespread use in many applications. For example, in the infant and child care areas, diapers and training pants have generally replaced reusable cloth absorbent articles. Other typical disposable absorbent products include feminine care products such as sanitary napkins or tampons, adult incontinence products, and health care products such as surgical drapes or wound dressings. A typical disposable absorbent product generally comprises a composite structure including a liquid-permeable topsheet, a fluid acquisition layer, an absorbent structure, and a liquid-impermeable backsheet. These products usually include some type of fastening system for fitting the product onto the wearer.
Disposable absorbent products are typically subjected to one or more liquid insults, such as of water, urine, menses, or blood, during use. As such, the outer cover materials of the disposable absorbent products are typically made of liquid-insoluble and liquid impermeable materials, such as polypropylene films, that exhibit a sufficient strength and handling capability so that the disposable absorbent product retains its integrity during use by a wearer and does not allow leakage of the liquid insulting the product.
Although current disposable baby diapers and other disposable absorbent products have been generally accepted by the public, these products still have need of improvement in specific areas. For example, many disposable absorbent products can be difficult to dispose of. For example, attempts to flush many disposable absorbent products down a toilet into a sewage system typically lead to blockage of the toilet or pipes connecting the toilet to the sewage system. In particular, the outer cover materials typically used in the disposable absorbent products generally do not disintegrate or disperse when flushed down a toilet so that the disposable absorbent product cannot be disposed of in this way. If the outer cover materials are made very thin in order to reduce the overall bulk of the disposable absorbent product so as to reduce the likelihood of blockage of a toilet or a sewage pipe, then the outer cover material typically will not exhibit sufficient strength to prevent tearing or ripping as the outer cover material is subjected to the stresses of normal use by a wearer.
Furthermore, solid waste disposal is becoming an ever increasing concern throughout the world. As landfills continue to fill up, there has been an increased demand for material source reduction in disposable products, the incorporation of more recyclable and/or degradable components in disposable products, and the design of products that can be disposed of by means other than by incorporation into solid waste disposal facilities such as landfills.
As such, there is a need for new materials that may be used in disposable absorbent products that generally retain their integrity and strength during use, but after such use, the materials may be more efficiently disposed of. For example, the disposable absorbent product may be easily and efficiently disposed of by composting. Alternatively, the disposable absorbent product may be easily and efficiently disposed of to a liquid sewage system wherein the disposable absorbent product is capable of being degraded.
Although degradable monocomponent fibers are known, problems have been encountered with their use. In particular, known degradable fibers typically do not have good thermal dimensional stability such that the fibers usually undergo severe heat-shrinkage due to the polymer chain relaxation during downstream heat treatment processes such as thermal bonding or lamination.
In contrast, polyolefin materials, such as polypropylene, typically exhibit good thermal dimensional stability but also have problems associated with their use. In particular, polyolefin fibers typically are hydrophobic and, and such, exhibit poor wettability, thus limiting their use in disposable absorbent products intended for the absorption of fluids such as body fluids. Although surfactants can be used to improve the wettability of polyolefin fibers, the use of such surfactants introduces additional problems such as added cost, fugitivity or permanence, and toxicity. Furthermore, polyolefin fibers are generally not biodisintegratable or compostable.
Additionally, breathability is an important aspect for personal care articles. For example, breathability in a diaper provides significant skin health benefits to the baby wearing the diaper. Moisture vapors are allowed to pass through the outer cover, leaving the baby's skin drier and less prone to diaper rash.
It would therefore be desirable to prepare a breathable, biodegradable/compostable laminates for personal care products. The biodegradable/compostable laminates may be used in a disposable absorbent product intended for the absorption of fluids such as body fluids.